﻿GEOLOGY 
  OF 
  THE 
  NORTH 
  CREEK 
  QUADRANGLE 
  69 
  

  

  wholly 
  derived 
  from 
  without 
  the 
  quadrangle, 
  and 
  especially 
  abund- 
  

   ant 
  in 
  its 
  northern 
  portion, 
  is 
  the 
  coarse 
  grained 
  anorthosite 
  whose 
  

   nearest 
  parent 
  ledges 
  are 
  in 
  the 
  northern 
  portion 
  of 
  the 
  Schroon 
  

   lake 
  sheet. 
  Such 
  boulders 
  several 
  feet 
  across 
  are 
  frequently 
  en- 
  

   countered. 
  The 
  only 
  Paleozoic 
  rock 
  boulders 
  noted 
  were 
  of 
  Pots- 
  

   dam 
  sandstone 
  and, 
  as 
  already 
  stated, 
  these 
  are 
  nearly 
  all 
  confined 
  

   to 
  the 
  Hudson 
  valley 
  between 
  Heath 
  and 
  Moon 
  mountains. 
  

  

  Glacial 
  till 
  or 
  ground 
  moraine 
  material 
  is 
  quite 
  widespread, 
  

   especially 
  over 
  the 
  lowlands, 
  but 
  no 
  great 
  thickness 
  was 
  noted 
  at 
  

   any 
  place. 
  It 
  would 
  seem 
  that 
  more 
  material 
  was 
  scraped 
  off 
  by 
  

   ice 
  erosion 
  than 
  was 
  deposited 
  as 
  till. 
  As 
  would 
  be 
  expected 
  from 
  

   the 
  nature 
  of 
  the 
  rocks, 
  the 
  till 
  is 
  always 
  sandy 
  or 
  gravelly 
  and 
  gen- 
  

   erally 
  filled 
  with 
  boulders. 
  Not 
  a 
  single 
  good 
  example 
  of 
  real 
  

   boulder 
  clay 
  was 
  observed. 
  

  

  Karnes 
  are 
  of 
  uncommon 
  occurrence. 
  Three 
  or 
  four 
  good 
  ones, 
  

   large 
  enough 
  to 
  be 
  shown 
  by 
  the 
  contour 
  lines, 
  lie 
  in 
  the 
  little 
  val- 
  

   ley 
  a 
  mile 
  west 
  of 
  No. 
  9 
  mountain. 
  Some 
  other 
  stratified 
  sand 
  and 
  

   gravel 
  deposits 
  of 
  rather 
  doubtful 
  kame 
  origin 
  occur 
  in 
  the 
  valley 
  

   between 
  Chestertown 
  and 
  Tripp 
  pond. 
  

  

  But 
  one 
  fairly 
  well-defined 
  boulder 
  moraine 
  came 
  to 
  the 
  writer's 
  

   notice 
  and 
  this 
  is 
  quite 
  clearly 
  traceable 
  as 
  a 
  belt 
  1 
  to 
  3 
  miles 
  wide 
  

   from 
  the 
  vicinty 
  of 
  South 
  Horicon 
  westward 
  around 
  Prospect 
  

   mountain, 
  thence 
  across 
  the 
  southern 
  part 
  of 
  Loon 
  lake 
  and 
  a 
  

   mile 
  or 
  so 
  southward, 
  thence 
  over 
  the 
  southern 
  end 
  of 
  the 
  ridge 
  

   just 
  west 
  of 
  the 
  lake, 
  and 
  nearly 
  to 
  the 
  river. 
  The 
  ice 
  front 
  must 
  

   liave 
  been 
  nearly 
  stationary 
  for 
  some 
  time 
  along 
  this 
  line 
  to 
  allow 
  

   the 
  accumulation 
  of 
  so 
  many 
  boulders. 
  

  

  GLACIAL 
  LAKES 
  

  

  Glacial 
  Lake 
  Warrensburg. 
  This 
  extinct 
  glacial 
  lake, 
  recently 
  

   described 
  by 
  the 
  writer, 
  is 
  so 
  named 
  because 
  of 
  the 
  location 
  of 
  the 
  

   village 
  of 
  Warrensburg 
  upon 
  the 
  old 
  lake 
  deposit 
  which 
  is 
  especially 
  

   well 
  shown 
  as 
  a 
  sand 
  plain 
  area 
  between 
  the 
  village 
  and 
  the 
  Hud- 
  

   son 
  river. 
  The 
  concordant 
  altitudes 
  of 
  this 
  sand 
  flat, 
  where 
  un- 
  

   affected 
  by 
  subsequent 
  erosion; 
  the 
  remarkable 
  freedom 
  of 
  the 
  

   surface 
  from 
  boulders; 
  and 
  the 
  crudely 
  stratified 
  character 
  of 
  the 
  

   material 
  as 
  shown 
  in 
  cuts 
  all 
  afford 
  conclusive 
  evidence 
  for 
  static 
  

   water 
  conditions 
  here, 
  the 
  sand 
  plain 
  material 
  having 
  been 
  formed 
  

   as 
  a 
  delta 
  deposit 
  in 
  the 
  lake. 
  This 
  is 
  a 
  good 
  example 
  of 
  a 
  small 
  

   pitted 
  sand 
  plain, 
  there 
  being 
  two 
  notable 
  depressions 
  (one 
  con- 
  

  

  